Contain Cobalt

Cobaltill) hydroxide is obtained as a precipitate when hydroxide ion is added to a solution containing cobalt(II) ions. The precipitate is often blue, but becomes pink on standing it dissolves in excess alkali to give the blue [CofOH) ion, and in slightly alkaline solution is easily oxidis by air to a brown solid of corttposition Co "0(OH). 

It is alloyed with iron, nickel and other metals to make Alnico, an alloy of unusual magnetic strength with many important uses. Stellite alloys, containing cobalt, chromium, and tungsten, are used for high-speed, heavy-duty, high temperature cutting tools, and for dies. 

The first iron—nickel martensitic alloys contained ca 0.01% carbon, 20 or 25% nickel, and 1.5—2.5% aluminum and titanium. Later an 18% nickel steel containing cobalt, molybdenum, and titanium was developed, and still more recentiy a senes of 12% nickel steels containing chromium and molybdenum came on the market. 

Cobalt(II) can be separated from cobalt(III) as the acetylacetonate (acac) compounds by extraction of the ben2ene soluble cobalt(Ill) salt (14). Magnesium hydroxide has been used to selectively adsorb cobalt(Il) from an ammonia solution containing cobalt(Il) and cobalt(Ill) (15). 

Shell Gas B.V. has constructed a 1987 mVd (12,500 bbhd) Fischer-Tropsch plant in Malaysia, start-up occurring in 1994. The Shell Middle Distillate Synthesis (SMDS) process, as it is called, uses natural gas as the feedstock to fixed-bed reactors containing cobalt-based cat- yst. The heavy hydrocarbons from the Fischer-Tropsch reactors are converted to distillate fuels by hydrocracking and hydroisomerization. The quality of the products is very high, the diesel fuel having a cetane number in excess of 75. 

Cobalt Compounds - Includes any unique chemical substance that contains cobalt as part of that chemical s infrastructure. 

More than 200 ores are known to contain cobalt but only a few are of commercial value. The more important are arsenides and sulfides such as smaltite, C0AS2, cobaltite (or cobalt glance), CoAsS, and linnaeite, C03S4. These are invariably associated with nickel, and often also with copper and lead, and it is usually obtained as a byproduct or coproduct in the recovery of these metals. The world s major sources of cobalt are the African continent and Canada with smaller reserves in Australia and the former USSR. All the platinum metals are generally associated with each other and rhodium and iridium therefore occur wherever the other platinum metals are found. However, the relative proportions of the individual metals are by no means constant and the more important sources of rhodium are the nickel-copper-sulfide ores found in South Africa and in Sudbury, Canada, which contain about 0.1% Rh. Iridium is usually obtained from native osmiridium (Ir 50%) or iridiosmium (Ir 70%) found chiefiy in Alaska as well as South Africa. 

Fig. 13.2 Linear plats of the effect of current density an the porasity, expressed as p.p.m. Cu, for three different gald-plating baths. The numbers next ta each point show the actual average thickness Orm) for each test. Bath A was a proprietary alkaline cyanide bath using silver as a brightener. Bath D was an acid gold bath containing cobalt and an ethylenediamine tetraacetic...

Colour centres in alkali borate glasses containing cobalt, nickel and copper. R. Juza, H. Seidel and J. Tiedemann, Angew. Chem., Int. Ed. Engl., 1966, 5, 85-94 (44). 

The seminal studies on these complex compounds were conducted by Alfred Werner in an intensive period of work at the turn of the century. A typical example of the problems that Werner addressed lies in the various compounds which can be obtained containing cobalt, ammonia and chlorine. Stable and chemically distinct materials with formulations Co(NH3) Cl3 (n = 4,5 or 6) can be isolated. The concepts of valency and three-dimensional structure in carbon chemistry were being developed at that time, but it was apparent that the same rules could not apply to... 

The reactions which are catalyzed by enzymes containing cobalt corrinoids can be classified into three groups. 

It has been known for some time (60-63) that aqueous ammonia solutions containing cobalt(II) salts turn brown on exposure to air. Thermodynamic (64) and kinetic (65, 66) studies on cobalt(II) ammines have therefore been carried out in inert atmosphere. 

A large number of type 1 dioxygen adducts are reported in the literature (25, 76, 80). The vast majority of metal complexes which take up dioxygen to form type I adducts contain cobalt(ll) as the metal ion. Ochiai (81) considered the hypothetical reactions ... 

Separation of two metals from a leach solution - as examples, mention may be made of solutions containing cobalt and copper, and nickel and copper. The former solution is treated by metallic cobalt to precipitate copper, and the latter by metallic nickel to precipitate copper. In both cases, the metal added to cement the copper is recovered afterwards. 

Another issue with metals is availability. For example, cobalt is not produced in the United States, but it used extensively in a wide variety of alloys and in the production of one of the most common types of lithium batteries. The availability of cobalt is crucial to several segments of American industry. For example, batteries being developed for use in automobiles powered by alternate energy sources are currently envisioned to use a lithium ion battery that also contains cobalt. However, cobalt is not the only strategic metal, and there is concern about the availability of several metals that are vital to industries in the United States, China, and Japan. There will be competition and stockpiling of strategic metals as the reserves become less accessible. 

Further development of this aerobic oxidation was done by utilizing a quinone containing cobalt tetraphenyl porphyrin47. This gives a more efficient electron transfer between quinone and porphyrin and results in a faster aerobic 1,4-diacetoxylation of the diene. The... 

Ferroflning A mild hydrotreating process for purifying lubricating oils. The catalyst contained cobalt, molybdenum, and iron (hence the name). Developed by the British Petroleum Company and first operated in Dunkirk, England in 1961. 

Litol Also called Houdry-Litol. A process for making benzene by dealkylating other aromatic hydrocarbons. It is a complex process which achieves desulfurization, removal of paraffins and naphthenes, and saturation of unsaturated compounds, in addition to dealkylation. The catalyst contains cobalt and molybdenum. Developed by the Houdiy Process and Chemical Company and Bethlehem Steel Corporation. First installed by the Bethlehem Steel Corporation in 1964. Subsequently used at British Steel s benzole refinery, Teesside, England. 

These ores also contain cobalt minerals, mainly carrollite (C0CUSO4) and cobaltite (CoAsS). 

Irrespective of the exact configuration around the promoter atom, we have a detailed picture of the Co-Mo-S phase on the atomic scale. Figure 9.23 summarizes schematically what a working Co-Mo/A1203 hydrodesulfurization catalyst looks like. It contains MoS2 particles with dimensions of a few nanometers, decorated with cobalt to form the catalytically highly active Co-Mo-S phase. It also contains cobalt ions firmly bound to the lattice of the alumina support, and it may contain crystallites of the stable bulk sulfide Co9S8, which has a low activity for the HDS reaction [49]. 

As shown in Table 12 all the dodecacarbonyls containing cobalt are sensitive to Lewis bases, which tend to induce disproportionation. This behaviour is well documented for Co2(CO)s 39 but has been much less studied in the case of Co4(CO)i2 ... 

Occurrence. There are a number of important ores containing cobalt. These include linnaeite, Co3S4, cobaltite, CoAsS, and smaltite, CoAs2. 

Occurrence. Arsenic is associated with sulphide minerals (As4S4 realgar, As2S3 orpiment, FeAsS arsenopyrite, Cu3AsS4, enargite, etc.). Occasionally arsenic is found as free element, usually in ore containing cobalt, antimony, nickel. 

An oxidation catalyst containing cobalt, copper, manganese and silver species. It adsorbs nitroalkanes strongly, which may then ignite. Respirator cartridges containing it should not be used in high concentrations of nitroalkanes. 

Heteroatom-containing (cyclobutadiene)Co complexes (e.g. 237, 238 and 239) have been prepared by the reaction of heteroatom containing cobalt precursors with dipheny-lacetylene or by the reaction of cobalt precursors with phospha-alkynes228. 

For hydrogenation in water with an inexpensive catalyst, solutions containing cobalt salts and excess cyanide are useful10,11. The catalysts are selective for conjugated C=C bonds and are relatively unreactive with unconjugated dienes such as 1,5-cyclooctadiene. 

Like many vitamins, cobalamin is functionally active as a derived coenzyme, coenzyme B12. Structurally, this is composed of a corrin ring a haem-like porphyrin ring containing cobalt (Co3+) at the centre held by four coordination bonds. The fifth... 

CO Subsequently a migratory insertion will take place. Oxidative addition of H2 will be faster at the electron rich metal centre and thus the aldehyde will form. Hydrogenation takes place at ruthenium (added as Ru3(CO)i2) as indeed catalyst systems containing cobalt only are known to give 3-hydroxypropanal as the product. 

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